All species are scented with coumarin (C9H6O2), and some are used medicinally for their coumarin content.

Hierochloë has traditionally been recognized on the basis of the two lower florets being staminate, paleate, and awnless or only shortly awned, in contrast to the sterile, epaleate, geniculately awned lower florets in typical Anthoxanthum. Lodicules are also absent in typical Anthoxanthum. However, it is now known that a considerable number of species is intermediate in these characters, including some in China, and also some (e.g., A. hookeri) where the sex of the lower florets is variable within the species. There is no justification for continuing to recognize two separate genera. The species are all clearly related by their unusual spikelet structure and by the presence of coumarin.

About 50 species:temperate and cold regions of both hemispheres, also on tropical mountains; ten species (three endemic) in China.